


i've no need to live if you're to come up gone

by MajorEnglishEsquire



Category: Supernatural
Genre: Angst, Blood and Gore, M/M, Mark of Cain, Season/Series 10, Suicidal Thoughts
Language: English
Status: Completed
Published: 2014-12-03
Updated: 2014-12-03
Packaged: 2018-02-28 00:13:12
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 3,274
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2711903
Author URL: https://archiveofourown.org/users/MajorEnglishEsquire/pseuds/MajorEnglishEsquire
Summary: <blockquote class="userstuff">
              <p>Based on the preview for 10.09, The Things We Left Behind</p><p> </p><p>  <i>If I go dark side, you gotta take me out</i></p>
            </blockquote>





	i've no need to live if you're to come up gone

**Author's Note:**

> I do not own the rights to these characters, setting, show, etc. No harm is intended.

_Dark Side_ , Cas thinks.

It's a trail from the sidewalk, meandering into the building.

Gore. Parts. Blood.

He follows. The action is long over. And when he reaches the room in the corner, there Dean kneels, breath caught up and using his left hand to pry the knife from his right hand.

Dark Side.

Castiel knows the _Star Wars_ movies. Well. Knows _of_ them, the knowledge forced upon him by Metatron.

It struck him how bloodless the Dark Side was when it fought. The clean slices of cauterizing plasma blades. Demon-like strength and choking constraint from a distance. Even with firearms, there were black-singed blast holes in bodies and not puddles everywhere. No bone fragments. No brain splatter.

So, even if he had promised, Castiel considers as he steps near, every step slow, clearly broadcast, deliberate--

Even if he had promised. He wouldn't have to do it.

Because this isn't the Dark Side. This isn't clean and neat. This isn't advanced combat with refined armaments.

Cas has seen the Dark Side. Been the Dark Side. Killed armies of angels with nothing more than black scorch marks and empty eyes. Killed them clean.

He knows the Dark Side.

He crouches in front of Dean and draws the sticky knife, tacky with viscera, away from Dean by the tip of the blade, and slides it away, across the floor.

Dean's heaving breaths slow as his eyes draw up. And what Cas sees in them is pleading and fear. He sees Dean getting lost in this.

The Dark Side feels no fear. Cas should know. Cas had no fear when he was playing god.

This isn't the Dark Side.

And he made no promises.

«»

He'd said, "You know I won't promise that," and Dean had looked at him like he'd change his mind. No more faith in himself than the day they'd met. Trusting only in the fact that death would come for him soon.

"No," he shook his head. "You pulled me out. You and Sam saved me from that. And I'm not going back to being a demon. You know you can't let me and you know that's not what I want. Promise me," Dean requested again.

Castiel had continued to refuse, mute, shaking his head, lips shut tight.

Dean had only stared at him, long and considering. Knowing how much Cas was always willing to give him. Sure that, in the moments when it counted most, Cas would do as he asked.

Dean knows himself no better than he ever did. Continues to doubt his own strength.

And Cas had thought Dean would come to know him. He thought they'd been friends (and enemies and comrades and fellow combatants) long enough that Dean would know him better. Would see the same resolution in his eyes as when the angels wanted him to punish Dean for Tessa's death and he had said, "No."

He says "no" again.  
He would not prove his loyalty to the angels by killing Dean.  
He will not prove his loyalty to _Dean_ by killing Dean.

«»

Castiel tries to get Dean to his feet, hands under his elbows, lifting him from the blood-spattered floor.

That's when he starts babbling.

"You have to" and "You've got to" and "I don't want to" and "Please, Cas" and "You can't let this happen again."

He is wrong, of course. Castiel can and would let it happen again. He's already learned that's what family really means: You'd rather see the one you love responsible for ending the lives of hundreds than face having to live without them. You'd rather the hurt keep coming than that they come to an end.

They'll find Sam and he won't let Dean worm away from it. He'll tell Sam what Dean asked him to do and he will be angry. He will be sad and mad and force Dean to see reason.

The power of the Mark surges through Dean when he's not even trying. That's the only way he's able to yank his arms from Cas's grasp and grab hold of his coat, haul him close, suddenly hissing up in his face, "If you don't do it, you know I'll kill everyone."

And all at once the fear is gone from his eyes. The stranger who'd rampaged through the bunker rises behind Dean's eyes and Cas feels his own face slacken in fear.

"You know I will," he- **it** insists. "It's over. I'll burn it all--"

Cas still has the better measure of strength and uses it to land a positively stunning blow to the side of Dean's head. He falls to the side, hits the floor hard, but doesn't stay down. The rage is already bringing him up again, fast, closer to the knife with one hand, the other grabbing for Castiel's throat.

The second blow knocks him out entirely.

«»

Cas can only imagine how Sam would crumple at seeing Dean strapped and trapped again.

So he puts him in the passenger seat as if he were simply sleeping and takes him back to a motel. The floor in the bathroom is tile and easy to draw on. The devil's trap isn't quite necessary yet. But it might be. So he straps Dean into a chair and keeps him by the sink. He uses a washcloth with cool water to wipe his face, clean the blood, tend to cuts, and, when he's ready, he heals the head bruising and wakes Dean.

The first is a look of betrayal. Whether he feels betrayed that Cas would restrain him or betrayed that he won't kill him, he can only guess.

Then shutdown. And silence.

Cas wets a new towel and rounds the chair to take care of the mess on Dean's hands and wrists. His fingers make no move to grab Cas or tear at the ropes. And when he comes around to face him again, he sees that the subtle shaking isn't just shock, but tears.

Cas kneels in front of him and wipes his face again. He knows Dean wouldn't want to weep in front of him. He doesn't like the way he looks or feels when his emotions surface. He doesn't like to give that much away.

He rests against Dean's knees and waits.

"Kill me now? Please?" Dean's voice is thin and wet.

"You know that Sam would never stop hunting me. And you should know by now that you could never die without me following."

Dean changes his expression, intentionally. He fakes an emotion and does so effectively. Cas has been witness to it enough to know its message: Loathing. Hatred. It is betrayed by another emotion he's having a hard time containing. So Cas doesn't believe it for a minute. He wants to yell, lean over Dean's knees and get right in his face to scream at him. It works up his throat and leads his jaw into a grind of teeth. He keeps his lips sealed until he knows himself better; until he knows what to say.

"You cannot make me kill you. You cannot hate me for not wanting to kill you. I need you. I _need you_ \-- you understand that?" he lays his right hand on Dean's face, willing him to recall, to read the message for what it is. "Sam and I. We need you. I need you," he says again. Because this is a language they share.

And he sees how difficult it is for Dean to keep pretending he hates. It melts back into a shine in his eyes. He's so unbearably scared right now.

"Let me get Sam," he starts, and immediately Dean shakes his head in the negative.

Cas thinks. Considers. "Let me find Cain," he says, instead.

"How much time do you have left, huh? How much mojo have you run through since your last recharge? You can't do that in time, Cas. This is happening right now. This is _now_. You _have to_. Or find someone who _will_."

The thought of a stranger killing Dean is, possibly, more enraging than even the Mark of Cain could fabricate in its victim.

Cas takes a minute to calm himself and breathe. He stays crouched there, runs his hands over Dean's knees, blood dried into the denim.

If he considers this, he will only do so if he's got some way of bringing Dean back.

The time for finding out how to shift or remove the Mark has passed. Dean's right. There's not enough time for Cas to go hunting for wherever Cain's disappeared to now.

Killing him and resurrecting him would take more strength and more friends than he has left. He'd sink into Crowley's realm and Cas would have no one to help him lay siege to the pit to gather him back up again.

He could perform last rites, get Dean blessed and confessed and hope it gets him into Heaven, even with the Mark's tendrils snared in his soul.

Would the angels help him bring Dean back down? Would the time in Heaven cleanse his soul and set him to rights?

Dean's been there before. It did nothing but take his hope away from him. Made him lose faith in his brother. Made him lose trust in their plan to stop the apocalypse.

That experience did a number on Cas, too, of course.

He can't imagine they'll find help above or below. And, killed outright, as a human or a demon, Dean would have no chance of getting into Purgatory, where he already knows an escape hatch exists.

Would Dean consent to being made into some sort of monster hybrid for that purpose?

But these thoughts are too far-flung from the point: that there is no benefit to Dean dying. That Sam would certainly not survive his brother's death intact and Cas would not have much left to live for, himself.

"You saw what I did Cas," Dean whispers. "I've lost it. I'm gone. It's happening. You have to put me down, man."

"That's not the 'Dark Side', Dean. It's a step away from possession. What you're doing isn't something you're absorbed in. It's covering you up. Muting you and taking you away from us."

"So, what? If it's possession, you gonna shoot me up with blood again? Come on, is that our temporary fix, now? How often? How much of that will my body be able to handle?"

Cas runs his thumbs over and over the knobs of Dean's knees, thinking.

He's thinking.  
That.

He's got mojo enough to put Dean into a comfortable sleep, first. And give him a painless death on the end of an angel blade.

Dammnit. Just like Metatron had. Slipping it into his chest and.

Cas experiences nausea, a rising bile like he never even did when he was human and picking through the trash for food.

He tries to picture it a different way. Turning Dean's face away from him and knifing him in the back. Or a different way. Burning Dean out.

His eyes have closed and to stop seeing these things he opens them, looks into Dean's desperately sad face.

"I am. Dean. I am so damn sorry. I can't. I can't do this. I won't," he says through his teeth.

"Then you have to find someone who-"

"I wouldn't let them. I wouldn't let anyone. I would destroy them."

He stands.

"You are not disposable. We'll figure this out."

When he moves around to untie him, Dean actually tries to twitch out of the way. He protests that it's too dangerous but Cas carefully unbinds him all the way and tosses the ropes aside. Dean doesn't do anything. With his hands no longer held in place, he just lets them drop and slumps there, looking up at Cas.

"We'll find Cain," Cas says.

"We won't. He doesn't want to be found. It was luck that the spell we found traced the Mark when we were looking for the blade."

"Tell me everything, then. We'll find him again. There must be a way. If he's still some kind of demon, there has to at least be a way to summon him."

"He won't. He won't come back, Cas. Not until."

The air goes absolutely still as Dean stops himself.

"Until," Cas prompts.

But Dean only shakes his head.

Cas bends and reaches for Dean's hands, pulls them up until he follows like he's some giant, fabric puppet.

He draws him from the bathroom and out toward the bed. They stand beside it while Dean just looks at it, like he'd prefer to dive in and be drowned by the covers. Or stuffed under the frame and crushed by it. Like he'd rather be dead.

Castiel would like to shake him and shake him _hard_ but he doesn't. And doesn't take his hands again, either, though something in him is screaming to be closer, to absorb what he can while Dean still lives. To use his body, if he must, to make Dean trust him, fall into him, allow himself to be kept.

Dean comes to some resolve. "Cain said he'd be back on his own. And when he came back it would be my job to use the First Blade on him. To end him, he said."

Plans arise in Cas's mind unbidden. Layers of strategy folding over one another. Blueprints of different paths to a solution. He needs more information, but this is a good start. This is good intel.

And relief leaks in. A crack that could easily let loose a flood. It tastes pure and sweet and almost physically staggers him.

Yes.

"Then, I do. I promise, Dean."

Dean's eyes come up, lighting just slightly. "You promise. You promise you'll end me?"

"I will. I will conceal you and convince the world that you're dead. I'll convince Sam, too, if I have to, and publicly demand the blade back from Crowley. I'll let it be known he has it and when Cain comes to him for his promised remedy, we'll have him. Trap him somehow. Contain him. And make him take the Mark back."

"So, you're not killing me. And you think you're gonna contain him? Even Crowley was afraid of him. Crowley, who worked _against Lucifer_ , was scared of this guy. We can't trap him, there's no way."

"No way you know of yet. No way you've seen," Cas protests, "There's got to be something. We have something he wants. He wants you to use the Blade to kill him."

"And what?!" Dean exclaims, "You think he's just gonna take it back and _not_ turn around and kill all of us when he's got the power again? _If_ he takes the Mark back? There's no way, Cas-- I. You can't be serious. You're making this way more complicated than it has to be. Dammnit, Cas," he throws up his arms. "You were gonna find a way to live. Or go back to Heaven. Or something! Anything but this. Stuck making patches in the world and slumming it with us." He shrugs. "It makes no sense. You just end me and. And it'll be all over. You can do this, Cas, I know you can. I know you're powerful enough. You've got it in you. Fuck, man, you're my best friend. I'm supposed to be able to _trust_ you."

"You _can_ trust me," Cas snaps. "You can trust me not to harm you because I _won't_ do it, Dean. No matter how much I want to give you, no matter how willing I am to sacrifice for you, I will not give you _that_. It's not up for debate."

Dean lunges almost into Castiel's face to hiss, "Well then fuck you. Then what is the fucking _point_ of you?"

"To love you. To protect you," Cas barks back.

And Dean tries. He really does. He tries to keep the flame kindled in his chest, Cas can watch it happen. He tries to stay angry. Tries to be livid. Tries to crank it up to rage. But that same something stops him again. It's shaken belief. Only Dean's beliefs are largely _poisonous_ and it's good they're being fractured. He believes he's unworthy. Can't be loved. Can't be good for anyone. And to have that understanding crushed rattles him.

Cas shakes his head watching it happen. Watching Dean work his jaw, trying to find something to shout. Trying to put denial into words when, at his heart, he doesn't want to deny anymore.

And he can't find the words either way. To crush Cas's opinion of him or to tell him he cares, too. And that's fine. All these words, that ridiculous promise Dean wanted out of him-- it's all noise.

Actions are what matter.

Cas crowds into him and leans up, to wrap both arms around Dean's shoulders and pull him in. He presses his face against Dean's cheek where he can still feel denials trying to work their way out of his mouth. He'd crush them if they emerged. But he hopes Dean can't voice them for now. He hopes to use the light in him to destroy those doubts, not smite Dean. Not harm his family.

Dean is resistant, still. But only at first. The strength in his arms when they finally circle Cas is certainly improved, like before. It is happening again. It really is. And Castiel's power will only decrease as Dean gets stronger once more.

"I will promise you something," Cas offers at his ear.

Dean sinks his nose into Castiel's neck before asking what this promise will be.

"To never give up on you. I promise to not leave you alone again."

Dean's whole body shudders and drops into Cas. He can take the weight. Holds them both up.

"We need back-up plans on top of back-up plans," Dean says, sounding resigned.

"We could use Sam for that. We need him. We need each other."

"We need to get you recharged. We gotta fix you. Can't-" Dean stops. Pulls back. "Can't lose you."

"There are things I can try."

Dean considers him for a long moment. "You might come back to me, anyway. You usually do. I know you think it's a punishment."

"It may be, yes. But if a punishment can't keep me from you. If death can't? You should accept that we're connected. That we work together. That we'll figure this out." He works his fingers into the tense muscles at the back of Dean's neck. "Stop giving up on me."

"I guess it's only fair. While you won't leave me alone. Won't give up on _me_."

Cas confirms this with a nod. "I need you to do something very tough for me."

Dean straightens to attention. "What do you need?"

"Tell me when something's wrong. Tell me when you're feeling on edge. When you can't take it. When you're lost or numb. You have to _speak_ for me, Dean."

Dean snorts and looks around the room. "You know me. Can't get me to shut up about my fucking feelings."

"I'll shut you up when I need you to. Until then, you have to talk. We have to plan and I need to monitor how far you're sliding."

" _You_ can make me shut up?" Dean laughs a little, short and light. "That a threat, Cas? 'Cause with how I've been lately, I'm not sure you could str-"

Cas is right.  
Of course he's right.

He can make Dean shut up when he needs to. Can pull their lips together and kiss into him until he's quiet.

"Not a threat," Cas sweeps three small kisses across his jaw. "That's me giving you a _promise_."

**Author's Note:**

> ([x](https://www.youtube.com/watch?v=R3BA7OXI8CA))


End file.
